1. Field of the Invention
The present invention relates to a diaphragm unit, a lens barrel, and an imaging apparatus.
2. Description of the Related Art
A diaphragm unit is known which is used in portable imaging apparatuses such as video cameras and digital still cameras or projection-based optical apparatuses such as liquid crystal projectors.
As such a type of diaphragm unit, a diaphragm unit is known which employs an iris diaphragm adjusting the size of a diaphragm opening by swinging plural diaphragm blades arranged around the diaphragm opening in cooperation. A diaphragm unit is also known in which two diaphragm blades are made to slide along a straight line perpendicular to an optical axis with the diaphragm opening interposed therebetween (see JP-A-2001-117133 (Patent Document 1)).